Method of treating raw cashew



the treated cashew nut shell liquid distilled at re.

of the water in said aqueous solution to the not is heated under reduced pres Patented Jul y lo, 1951 r I h UNITED sures PATENT OFFICE DETHOD F TREATING RAW CASHEW NUT SHELL LIQUID Solomon Caplan, New York, N. Y., assignor to The Harvel Corporation, a. corporation of New Jersey No Drawing. Application January 27, 1948, Serial No. 4,695 2 Claims. (Cl. 260 521) This invention relates to novel methods for and in factory practice is usually in the range of treating cashew nut shell liquid containing ni- -100 to 100100.

trogenous and mineral components and to prod- Employing the aforesaid ratios the cashew nut and dihydric phenom Another object of this 10 cashew nut shell liquid with said acidic agent may cashew nut shell liquid The treated cashewnut l6 ever, I prefer that this treatment he conducted at 2o S1021 which ma have m ed a i the ix residues WhlCh are liquid at room temperature step and the nfass is ga g gf g gs and may measure as low as 45-35% by weight of The treated cashew nut shell liquid produced 5 constant at least as great as 1 75x1 Illustrais employed, emu ions are formed and they m y ve examples of said agents are acetic acid hye centrifuged, whereby the resultant treated drochloric acld sulphuric acid, sodium acid sulcashew nut shell liquid containing 0-2% water phate, etc. The concentration of said acidic is removed from the aqueous Bolnponent agent in said aqueous solution is below that 40 it is n t de d t u e the centrifuging step, a

said acidic agent to the raw cashew nut shell and contains the mineral and nitrogenous comleast .2 part of sulphuric acid to 100 of cashew which e in solution in the a The nitrognutshell liquid and preferably .4 part of sulphuric n lls c mp unds may be recovered from the acid to 100 of cashew nut shell liquid and may aqueous solution if desired. When no organic be as high as desired, although in factory practice solvent is used, the cashew nut shell liquid phase doe not exceed 2 parts of sulphuric acid to 100 which has been separated from the aqueous soluof cashew nut shell liquid. The ratio by weight tion usually contains 02% of water. This prodcashew nut shell liquid to be treated is preferably to drive off the water without increasing the visat least 10100 and may be as high as desired cosl'ty at 25 C. above that of the which is the non-aqueous phase from the aqueous phase, the pH of the aqueous phase value never below that l qu by the method or it may of commerce generally obtained typ set No.

by the hot exforth in the 2,058,456 and of anacardic either of these part acid, or it may be icular types artially or completely decarwhich have been boxylated.

The following examples are given by way of illustrating the invention and. therefore. are not to be regarded in a limiting sense.

Example 1 500 grams raw cashew nut shell liquid 200 grams aqueous solution H1804 containing H2804 are placed in a lead lined autoclave equip ed with an agitator. The mixture is heated with constant stirring to a temperature of about 300-325 F. whereupon the gauge pressure indicates '70 lbs. per square inch. The heating and stirring are sto and the mass is allowed to cool to room temperature. The mass is then found to have separated into two main layers: an aqueous layer and a non-aqueous layer of cashew nut shell liquid. is drawn oil. A comparison of the viscosity of the raw cashew nut shell liquid with that of the so-treated cashew nut shell liquid is as follows:

Viscosity of raw cashew nut shell liquid, 1'12 centipoises at C.

Viscosity of treated cashew nut shell liquid, 110

- centipoises at 25 C.

Example 2 cashew nut shell liquid containing heated shell liquid witha The aqueous layer 1 H180; containing 2% 4 cosity of the raw cashew nut shell liquid with that of the so-treated cashew nut shell liquid shows:

Viscosity of raw cashew nut shell liquid, 265

centipoises at 25 C.

Viscodty of treated cashew nut shell liquid, 188

centipoises at 25 C.

Example 3 500 grams raw cashew nut shell liquid are treated with 200 grams of an aqueous solution of H2804 in the same manner as that set forth in Example 2. A comparison of the viscosity of the raw cashew nut shell liquid of the so-treated cashew nut shell liquid gave the following results:

Viscosity of raw cashew nut shell liquid, 222

centipoises at 25 C.

Viscosity of treated cashew nut centipoises at 25 0.

Example 4 500 grams of raw cashew nut shell liquid are with 200 grams aqueous solution of HCl containing 10% HCl in the same manner as that set forth in Example 2. Comparison of the viscosity of the raw cashew nut shell liquid with that of the treated cashew nut shell liquid showed:

Viscosity of raw cashew nut shell liquid, 222

centipoises at 25 C.

Viscosity of treated cashew nut centipoises at 25 C.

Example 5 500 gram portions of raw cashew nut shell liquid were treated with 200 cc. portions of aqueous solution containing the following acids in the shell liquid, 124

shell liquid 184 percentages indicated and following the procedure set forth in Example 2.

Per cent Dichloracetic acid a.. 4 Dichloracetic acid 3 Monochloracetic acid 3 Phosphoric acid 5 Phosphoric acid 2 Acetic acid 3 Acetic acid 2 Treated cashew nut shell liquids were produced whose viscosities were in every instance lower than that of the raw cashew nut shell liquid employed.

Example 6 The proportions of materials being the same as those set forth in the preceding examples and carrying out the mixing at room temperature in each instance and then thereafter breaking the resultant emulsions by heating preferably at a temperature between -210 F. and then allowing the mass to stand, it will separate into two main layers. After the water layer has been removed in each instance the resultant sotreated cashew nut shell liquid will be found to have a reduction in viscosity of more than 10% when compared to the viscosity of the raw cashew nut shell liquid employed.

Example 7 and 50 lbs. toluene and oughly agitated for about Viscosity of raw cashew centipoises at 25 C. Viscosity of treated cashew nut shell liquid, 160

centipoises at 25 c.

Example 8 Viscosity of raw centipoises at 2 c.

Viscosity of treated cashew nut shell liquid, 244

centipoises at 25 C.

By following the teachings of this invention as exemplified in Examples 1-8 there may be procashew nut shell liquid which is capable of being precipitated by means of diethyl sulphate. 1'

traces of those components, the treated nut shell liquid One method, to heat the treated cashew nut F. under reduced presmercury. Another treated is completely eliminated therefrom without increasing its viscosity at 25 C. above that of the raw cashew nut shell liquid from which it was derived.

11 as polymers thereof.

claim:

crease the viscosity of the cashew nut shell liq uid at 25 C. when maintained constant of the ratio by weight of said for 3 hours and then removing from said mass cashew nut shell SOLOMON CAPLAN.

REFERENCES CITED The following references are of record in the file 01' this patent:

UNITED STATES PATENTS Number Name Date 2,067,919 Harvey et al. Jan. 19, 1937 2,128,247 Harvey et a1 Aug. 30, 1938 2,223,549 Harvey Dec. 3, 1940 2,240,034 Caplan Apr. 29, 1941 2,401,095 Novotny May 28, 1946 OTHER REFERENCES Harvey et al., Ind. & Eng. Chem, vol. 32. pp. 1306-1309 (1940).

asserman et al., Ind. and Eng. Chem. vol. 37, pp. 396-398 (1945). 

1. THE METHOD OF REMOVING FROM RAW CASHEW NUT SHELL LIQUID NITROGENOUS AND MINERAL COMPONENTS NORMALLY PRESENT THEREIN COMPRISING MIXING SAID CASHEW NUT SHELL LIQUID WITH AN AQUEOUS SOLUTION OF AN ACIDIC AGENT IONIZATION CONSTANT OF SAID AGENT BEING AT LEAST 1.75X10-5 